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Misfire P0300

flame102
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8 years 6 months ago #10580 by flame102

Misfire P0300 was created by flame102

2012 chevy Silverado 3500 6.0l,scanner shows 30 misfire on #4 cly. short terms readings are good..compression good .
swapped one at a time coil,wire ,plug to a good cyl. no change.check for vacuum leaks, no leaks ... Any suggestions ??

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cheryl hartkorn
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8 years 6 months ago #10584 by cheryl hartkorn

Replied by cheryl hartkorn on topic Misfire P0300

injector flow test yet?

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cheryl hartkorn
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8 years 6 months ago #10585 by cheryl hartkorn

Replied by cheryl hartkorn on topic Misfire P0300

vacuum reading nice and steady?

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Ben
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8 years 6 months ago #10607 by Ben

Replied by Ben on topic Re:Misfire P0300

An injector flow test would be a good step, it sounds like you've covered ignition pretty well

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Tyler
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8 years 6 months ago #10616 by Tyler

Replied by Tyler on topic Re:Misfire P0300

Is this a misfire you can reproduce, or are you just seeing the misfire history? Freeze frame data might be useful in this situation.

I have seen AFM lifters fail intermittently, but you have to catch it in the act to prove it.

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flame102
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8 years 6 months ago #10674 by flame102

Replied by flame102 on topic Misfire P0300

Have not done a injector bal,but I have disconnected the injector and the misfires counts go up from 30 to 120 and it feels like is missing worse.

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flame102
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8 years 6 months ago #10675 by flame102

Replied by flame102 on topic Misfire P0300

vacuum is steady on the scanner ,{Have not used a manual gauge} ...

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